Pincer for gripping the upper of a boot or shoe during lasting



Oct. 21, 1970 G. SOMMER 3,535,723

FINGER FOR GRIPPING THE UPPER OF A BOOT OR SHOEDURING LASTING Filed Jan 8, 1969 INVENTOR. GeraL Summer United States Patent 3,535,723 PINCER FOR GRIPPING THE UPPER OF A BOOT 0R SHOE DURING LASTING Gerald Sommer, Erleubrunu, Germany, assignor, by mesne assignments, to Fir-ma Eugen G. Henkel, Maschinenfabrik, Neu-Isenburg, Germany, and Compo Industries, Inc., Waltham, Mass., jointly Filed Jan. 8,1969, Ser. No. 789,890 Claims priority, application Germany, Jan. 9, 1968, 1,685,416 Int. Cl. A43d 23/00 US. Cl. 12-145 4 Claims ABSTRACT OF THE DISCLOSURE The specification describes a pincer for gripping the uppers of boots or shoes during lasting. A pincer head provided with hydraulically operable claws, is mounted on a carrier securable to the lasting machine, by means of a ball joint which permits the pincer head to be pivoted in three mutually perpendicular planes, and then to be locked in a desired pivotal position.

The invention relates to a pincer for gripping the edge of a boot or shoe upper during lasting, in particular in the zone corresponding to the ball of the foot.

In lasting machines for boots or shoes, it is known to use a variety of pincers which grip the material of the upper, pull it over and carry it under the last, where the upper material is lasted with the insole. Since the design of the last varies widely, depending on the boot or shoe to be manufactured, the pincer must have a wide range of adjustment possibilities. Thus, devices are known which permit a translatory displacement of the pincer means in a horizontal plane, parallel to the longitudinal axis of the last and perpendicular to the said plane.

According to the present invention there is provided a pincer for gripping the edge of a boot or shoe upper, during lasting, said pincer comprising a pincer head adapted to grip the upper, a carrier mountable on a lasting machine and a pivotal connection between the carrier and the pincer head permitting the pincer head to pivot with respect to the carrier in three mutually perpendicular planes.

A pincer according to the present invention, enables the upper material to be brought smoothly, up to the last base, also in the zone behind the zone corresponding to the ball of the foot and towards the shank or waist. This is advantageous, since the last, firstly, narrows to a varying degree from the ball zone towards the shank and, secondly, extends vertically away, to a varying degree from the horizontal last plane, and thirdly is curved to a varying degree relatively to the horizontal last base plane perpendicular to the longitudinal axis of the last.

Unless a pincer according to the invention is used, there is a tendency for the upper material, during the adhesive lasting of the boot-toe, only to draw closely about the insole edges from the boot-toe as far as the ball zone, whereas it is not guided in the portion behind the ball zone towards the shank, so that, in the ball zone plane it ceases to follow the narrowing or constriction of the insole towards the shank and is therefore defectively stuck in the last portion of the ball zone. Thus, before the next-following shank lasting operation, the ends of the upper projecting towards the shank, about the defectively stuck portion in the shoe-ball portion, must once again be detached from the insole, in order that the upper material may, in the entire shank portion, be drawn without wrinkles and closely about the insole.

However, by using a pincer according to the invention, the pincer claws of the pincer head are adjustable in such "ice manner that they are able to bring up and smoothly apply the upper material to each component part of a last such as is provided in practice, so that the outer claw edges are adjustable as far as possible parallel to the insole edge of the associated last component part and displaceable towards the base at an angle located in a plane extending perpendicular to the said base part and depending on the convexity of the insole base in this component part of the last.

The pivotal connection may be constituted in various Ways. For example, the pincer head may be secured, via two hinges arranged one below the other and having vertical pivot planes which are perpendicular to each other, on the moving part of a pivoting or swiveling device having a horizontal pivot or swivel plane and the fixed lower portion of which is connected with the carrier. According to a preferred embodiment of pincer according to the invention, the connection between the pincer head and the carriers is eifected by means of a ball joint. With this arrangement, for the adjustment of the pincer, provision may additionally be made for translatory adjustment of the carrier in three mutually perpendicular directions.

In order that the invention may more readily be under stood, the following description is given, merely by way of example, reference being made to the accompanying drawing, in which the only figure is a section through one embodiment of pincer according to the invention.

A carrier 1 is connected to a pincer head 2 by means of a ball joint 3. As can be seen, the carrier includes a slide bed 4 having a pin 5 which, in use, is guided in an elongated recess formed in a mounting plate of the lasting machine substantially parallel to the longitudinal axis of the last. With this arrangement, the pincer is, as a whole, displaceable along the last edge and may be locked in the selected position by means of an eccentric 13.

Displaceably arranged on the carrier slide bed 4 is a carrier slide 7 which, by means of a spindle 8 actuated by a hand wheel 9, is displaceable substantially perpendicular to the longitudinal axis of the last. The spindle passes through a bore 10 in the carrier slide bed 4 and is secured against axial displacement by means of two circlips 11, and engages with a screwthread 12 on the carrier slide 7, which carries a vertical threaded post 14 formed with an axial bore 15.

Arranged for sliding in this bore is a guide cylinder 16 having, at its lower end, a pin 17 engaging in an axial recess 18 formed in the threaded cylinder 14. A sleeve 19 is threaded onto the post 14, and is located against axial movement, with respect to cylinder 16 by the pin 17 and by the first part 20 of a two part ball cage, which is secured to the guide cylinder 16. A rotational movement of the threaded sleeve 19 results in an axial displacement of the ball joint 3, which also included a second ball cage part 21 and a ball 22.

Parts 20 and 21 are connected by a screwthread 23, so that rotation of the part 21 with the aid of a lever 24, results in narrowing or widening of the ball cage. In this way, the ball joint may be locked in or released from any selected pivotal position. Connected with the ball is a pin 25 projecting through a conical recess 26 formed in the part 21, the apex angle of the conical recess 26 limiting the angular variation of the ball joint to a predetermined value such as is adequate for the variation required in the position of the pincer head, in accordance with the last designs available.

Mounted on the ball 22, via the screwthreaded portion portion of the pin 25, is a slide bed 27 of the pincer head. A slide 28, arranged for displacement in the slide bed 27, has rollers 29 sliding in slots 30 formed in the pincer slide bed. With the aid of a knurled screw 31 and a spindle 32 the stroke of the slide displacement in the slide bed 27 may be adjusted. Via a spring (not shown) the slide is drawn towards the slide bed stop. Adapted for connection via a bore 33 in the carrier slide 28 is a hydraulic control system acting on a piston 34, having a packing 35, which is guided in a cylindrical bore formed in the carrier slide 28. When pressure is applied, the rod 36 of the piston 34 bears on a slide bed stop 44.

A first pincer claw 37 is carried by the slide 28, and a second pincer claw 38, movable towards the fixed pincer claw 37, has a piston 39, having a packing 40, which is guided in a second cylindrical bore formed in the pincer slide 28. This cylinder bore is adapted to be connected, via a bore 41, with an hydraulic control system. A pin 42 on the movable pincer claw 38 slides in a slot 43 in the fixed pincer claw 37, thus ensuring exact guiding of the pincer claws relatively to one another.

In operation, the pincer head is brought adjacent the last by displacement of the pin 5 in the slot formed in the machine base substantially parallel to the longitudinal axis of the last, by rotation of the hand wheel 9, and by rotation of the threaded sleeve 19. After releasing the ball joint by actuation of the lever 24, the pincer head may be so adjusted that the outer edges of the pincer claws extend parallel to the last edge and the stroke direction of the pincer slide adopts an angle to the last plane which is determined by the convexity of the last portion. In this position, the pincer head is locked by actuating the lever 24. After the material of the upper has been introduced between the claws 37 and 38, hydraulic liquid is fed via the bore 41 to the piston 39, whereupon the claws close. During the pulling-over step, the claws pass into position under the last plane. Due to the action of the pressure fluid on the piston 34, the pincer slide travels obliquely under the last base, whereupon the desired lasting step may take place. After cutting off the pressure from the pistons 39 and 34, both the pincer claws 38 and also the pincer slide 28 are restored into their starting position by spring force.

Iclaim:

1. A pincer for gripping the edge of a boot or shoe upper during lasting, said pincer comprising, in combination:

(a) a pincer head effective to grip the upper;

(b) carrier means mountable on a lasting machine;

and

(c) pivotal connecting means operatively connecting A said carrier means to said pincer head whereby said pincer head is pivotal with respect to said carrier in three mutually perpendicular planes, said pivotal connecting means comprising a ball joint which itself compries:

(l) a ball cage having (i) a first part connected to said carrier, (ii) a second part, and (iii) screw means interconnecting said first and second parts, and (2) a ball within said ball cage connected to said pincer head, whereby rotation of said second part is effective to clamp said ball and therewith said pincer head in any selected position.

2'. A pincer for gripping the edge of a boot or shoe upper during lasting, said pincer comprising, in combination:

(a) a pincer head effective to grip the upper;

(b) carrier means mountable on a lasting machine;

(c) pivotal connecting means operatively connecting said carrier means to said pincer head whereby said pincer head is pivotal with respect to said carrier means in three perpendicular planes, said pivotal connecting means comprising a ball joint which comprises a ball cage and a ball within said ball cage connected to said pincer head;

(d) said pincer head comprising a slide bed secured to said ball, a slide slidable with respect to said slide bed, pincer claws on said slide, and means to operate said pincer claws.

3. A pincer as claimed in claim 2, wherein said pincer claws include one claw fixedly secured to said slide and a second claw movable with respect thereto, and wherein said operating means comprises a hydraulic actuating device.

4. A pincer as claimed in claim 2, wherein said carrier includes means for adjusting the translatory position thereof in three mutually perpendicular directions.

References Cited UNITED STATES PATENTS 1,280,613 10/1918 Ashton 12-145 X 1,347,929 7/1920 BagshaW 12-9 3,025,541 3/1962 Weinschenk 1214.5 X 3,099,846 8/1963 Lane et al. 12-10.l

PATRICK D. LAWSON, Primary Examiner 

